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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
- Cork the socket while there are queued replies
Fixes:
- DRC shutdown ordering
- svc_rdma_accept() lockdep splat
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Merge tag 'nfsd-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull more nfsd updates from Chuck Lever:
"Here are a few additional NFSD commits for the merge window:
Optimization:
- Cork the socket while there are queued replies
Fixes:
- DRC shutdown ordering
- svc_rdma_accept() lockdep splat"
* tag 'nfsd-5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
SUNRPC: Further clean up svc_tcp_sendmsg()
SUNRPC: Remove redundant socket flags from svc_tcp_sendmsg()
SUNRPC: Use TCP_CORK to optimise send performance on the server
svcrdma: Hold private mutex while invoking rdma_accept()
nfsd: register pernet ops last, unregister first
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Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Another nice round of removing more code than what is added, mostly
due to Christoph's relentless pursuit of tech debt removal/cleanups.
This pull request contains:
- Two series of BFQ improvements (Paolo, Jan, Jia)
- Block iov_iter improvements (Pavel)
- bsg error path fix (Pan)
- blk-mq scheduler improvements (Jan)
- -EBUSY discard fix (Jan)
- bvec allocation improvements (Ming, Christoph)
- bio allocation and init improvements (Christoph)
- Store bdev pointer in bio instead of gendisk + partno (Christoph)
- Block trace point cleanups (Christoph)
- hard read-only vs read-only split (Christoph)
- Block based swap cleanups (Christoph)
- Zoned write granularity support (Damien)
- Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"
* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
mm: simplify swapdev_block
sd_zbc: clear zone resources for non-zoned case
block: introduce blk_queue_clear_zone_settings()
zonefs: use zone write granularity as block size
block: introduce zone_write_granularity limit
block: use blk_queue_set_zoned in add_partition()
nullb: use blk_queue_set_zoned() to setup zoned devices
nvme: cleanup zone information initialization
block: document zone_append_max_bytes attribute
block: use bi_max_vecs to find the bvec pool
md/raid10: remove dead code in reshape_request
block: mark the bio as cloned in bio_iov_bvec_set
block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
block: remove a layer of indentation in bio_iov_iter_get_pages
block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
block: remove the 1 and 4 vec bvec_slabs entries
block: streamline bvec_alloc
block: factor out a bvec_alloc_gfp helper
block: move struct biovec_slab to bio.c
block: reuse BIO_INLINE_VECS for integrity bvecs
...
These pernet operations may depend on stuff set up or torn down in the
module init/exit functions. And they may be called at any time in
between. So it makes more sense for them to be the last to be
registered in the init function, and the first to be unregistered in the
exit function.
In particular, without this, the drc slab is being destroyed before all
the per-net drcs are shut down, resulting in an "Objects remaining in
nfsd_drc on __kmem_cache_shutdown()" warning in exit_nfsd.
Reported-by: Zhi Li <yieli@redhat.com>
Fixes: 3ba75830ce "nfsd4: drc containerization"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
In the typical case of v4 and an i_version-supporting filesystem, we can
skip a stat which is only required to fake up a change attribute from
ctime.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When exporting NFS, we may as well use the real change attribute
returned by the original server instead of faking up a change attribute
from the ctime.
Note we can't do that by setting I_VERSION--that would also turn on the
logic in iversion.h which treats the lower bit specially, and that
doesn't make sense for NFS.
So instead we define a new export operation for filesystems like NFS
that want to manage the change attribute themselves.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Currently NFSv4_2 SSC helper, nfs_ssc, incorrectly uses GRACE_PERIOD
as its config. Fix by adding new config NFS_V4_2_SSC_HELPER which
depends on NFS_V4_2 and is automatically selected when NFSD_V4 is
enabled. Also removed the file name from a comment in nfs_ssc.c.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I'm not sure why we're writing this out the hard way in so many places.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The set_client() was already taken care of by process_open1().
The comments here are mostly redundant with the code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Every caller is setting this argument to false, so we don't need it.
Also cut this comment a bit and remove an unnecessary warning.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I think this unusual use of struct compound_state could cause confusion.
It's not that much more complicated just to open-code this stateid
lookup.
The only change in behavior should be a different error return in the
case the copy is using a source stateid that is a revoked delegation,
but I doubt that matters.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ cel: squashed in fix reported by Coverity ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I think this is a better name, and I'm going to reuse elsewhere the code
that does the lookup itself.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
You can take the single-exit thing too far, I think.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Similarly, this STALE_CLIENTID check is already handled by:
nfs4_preprocess_confirmed_seqid_op()->
nfs4_preprocess_seqid_op()->
nfsd4_lookup_stateid()->
set_client()->
STALE_CLIENTID()
(This may cause it to return a different error in some cases where
there are multiple things wrong; pynfs test SEQ10 regressed on this
commit because of that, but I think that's the test's fault, and I've
fixed it separately.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This STALE_CLIENTID check is redundant with the one in
lookup_clientid().
There's a difference in behavior is in case of memory allocation
failure, which I think isn't a big deal.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Collect some nfsd stats per export in addition to the global stats.
A new nfsdfs export_stats file is created. It uses the same ops as the
exports file to iterate the export entries and we use the file's name to
determine the reported info per export. For example:
$ cat /proc/fs/nfsd/export_stats
# Version 1.1
# Path Client Start-time
# Stats
/test localhost 92
fh_stale: 0
io_read: 9
io_write: 1
Every export entry reports the start time when stats collection
started, so stats collecting scripts can know if stats where reset
between samples.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd stats counters can be updated by concurrent nfsd threads without any
protection.
Convert some nfsd_stats and nfsd_net struct members to use percpu counters.
The longest_chain* members of struct nfsd_net remain unprotected.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Commit 501cb1849f ("nfsd: rip out the raparms cache") removed the
code that updates read-ahead cache stats counters,
commit 8bbfa9f388 ("knfsd: remove the nfsd thread busy histogram")
removed code that updates the thread busy stats counters back in 2009
and code that updated filehandle cache stats was removed back in 2002.
Remove the unused stats counters from nfsd_stats struct and print
hardcoded zeros in /proc/net/rpc/nfsd.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Since the ACL GETATTR procedure is the same as the normal GETATTR
procedure, simply re-use nfssvc_decode_fhandleargs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that the argument decoders for NFSv2 and NFSv3 use the
xdr_stream mechanism, the version-specific length checking logic in
nfsd_dispatch() is no longer necessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If the code that sets up the sink buffer for nfsd_readlink() is
moved adjacent to the nfsd_readlink() call site that uses it, then
the only argument is a file handle, and the fhandle decoder can be
used instead.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The code that sets up rq_vec is refactored so that it is now
adjacent to the nfsd_read() call site where it is used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit removes the last usage of the original decode_sattr3(),
so it is removed as a clean-up.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Similar to the WRITE decoder, code that checks the sanity of the
payload size is re-wired to work with xdr_stream infrastructure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
As an additional clean up, neither nfsd3_proc_readdir() nor
nfsd3_proc_readdirplus() make use of the dircount argument, so
remove it from struct nfsd3_readdirargs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
De-duplicate some code that is used by both READDIR and READDIRPLUS
to build the dirlist in the Reply. Because this code is not related
to decoding READ arguments, it is moved to a more appropriate spot.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Code inspection shows that the server's NFSv3 READDIR implementation
handles offset cookies slightly differently than the NFSv2 READDIR,
NFSv3 READDIRPLUS, and NFSv4 READDIR implementations,
and there doesn't seem to be any need for this difference.
As a clean up, I copied the logic from nfsd3_proc_readdirplus().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
As part of the update, open code that sanity-checks the size of the
data payload against the length of the RPC Call message has to be
re-implemented to use xdr_stream infrastructure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The code that sets up rq_vec is refactored so that it is now
adjacent to the nfsd_read() call site where it is used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The next few patches will employ these strings to help make server-
side trace logs more human-readable. A similar technique is already
in use in kernel RPC client code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Prevent nfs from exporting idmapped mounts until we have ported it to
support exporting idmapped mounts.
Link: https://lore.kernel.org/linux-api/20210123130958.3t6kvgkl634njpsm@wittgenstein
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: "J. Bruce Fields" <bfields@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The various vfs_*() helpers are called by filesystems or by the vfs
itself to perform core operations such as create, link, mkdir, mknod, rename,
rmdir, tmpfile and unlink. Enable them to handle idmapped mounts. If the
inode is accessed through an idmapped mount map it into the
mount's user namespace and pass it down. Afterwards the checks and
operations are identical to non-idmapped mounts. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-15-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
In order to handle idmapped mounts we will extend the vfs rename helper
to take two new arguments in follow up patches. Since this operations
already takes a bunch of arguments add a simple struct renamedata and
make the current helper use it before we extend it.
Link: https://lore.kernel.org/r/20210121131959.646623-14-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.
Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.
Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
If you export a subdirectory of a filesystem, a READDIRPLUS on the root
of that export will return the filehandle of the parent with the ".."
entry.
The filehandle is optional, so let's just not return the filehandle for
".." if we're at the root of an export.
Note that once the client learns one filehandle outside of the export,
they can trivially access the rest of the export using further lookups.
However, it is also not very difficult to guess filehandles outside of
the export. So exporting a subdirectory of a filesystem should
considered equivalent to providing access to the entire filesystem. To
avoid confusion, we recommend only exporting entire filesystems.
Reported-by: Youjipeng <wangzhibei1999@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
While converting the NFSv4 decoder to use xdr_stream-based XDR
processing, I removed the old SAVEMEM() macro. This macro wrapped
a bit of logic that avoided a memory allocation by recognizing when
the decoded item resides in a linear section of the Receive buffer.
In that case, it returned a pointer into that buffer instead of
allocating a bounce buffer.
The bounce buffer is necessary only when xdr_inline_decode() has
placed the decoded item in the xdr_stream's scratch buffer, which
disappears the next time xdr_inline_decode() is called with that
xdr_stream. That happens only if the data item crosses a page
boundary in the receive buffer, an exceedingly rare occurrence.
Allocating a bounce buffer every time results in a minor performance
regression that was introduced by the recent NFSv4 decoder overhaul.
Let's restore the previous behavior. On average, it saves about 1.5
kmalloc() calls per COMPOUND.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
fs/nfsd/nfssvc.c:36:6: warning: symbol 'inter_copy_offload_enable' was not declared. Should it be static?
The parameter was added by commit ce0887ac96 ("NFSD add nfs4 inter
ssc to nfsd4_copy"). Relocate it into the source file that uses it,
and make it static. This approach is similar to the
nfs4_disable_idmapping, cltrack_prog, and cltrack_legacy_disable
module parameters.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If the READ_PLUS operation was truncated due to an error, then ensure we
clear the 'eof' flag.
Fixes: 9f0b5792f0 ("NFSD: Encode a full READ_PLUS reply")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Ensure that we encode the data payload + padding, and that we truncate
the preallocated buffer to the actual read size.
Fixes: 528b84934e ("NFSD: Add READ_PLUS data support")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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Merge tag 'fsnotify_for_v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
"A few fsnotify fixes from Amir fixing fallout from big fsnotify
overhaul a few months back and an improvement of defaults limiting
maximum number of inotify watches from Waiman"
* tag 'fsnotify_for_v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: fix events reported to watching parent and child
inotify: convert to handle_inode_event() interface
fsnotify: generalize handle_inode_event()
inotify: Increase default inotify.max_user_watches limit to 1048576
For the case of NFSv4, specify to the client that the pre/post-op
attributes were not recorded atomically with the main operation.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Don't set PF_LOCAL_THROTTLE on remote filesystems like NFS, since they
aren't expected to ever be subject to double buffering.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If the underlying filesystem times out, then we want knfsd to return
NFSERR_JUKEBOX/DELAY rather than NFSERR_STALE.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
It's not uncommon for some workloads to do a bunch of I/O to a file and
delete it just afterward. If knfsd has a cached open file however, then
the file may still be open when the dentry is unlinked. If the
underlying filesystem is nfs, then that could trigger it to do a
sillyrename.
On a REMOVE or RENAME scan the nfsd_file cache for open files that
correspond to the inode, and proactively unhash and put their
references. This should prevent any delete-on-last-close activity from
occurring, solely due to knfsd's open file cache.
This must be done synchronously though so we use the variants that call
flush_delayed_fput. There are deadlock possibilities if you call
flush_delayed_fput while holding locks, however. In the case of
nfsd_rename, we don't even do the lookups of the dentries to be renamed
until we've locked for rename.
Once we've figured out what the target dentry is for a rename, check to
see whether there are cached open files associated with it. If there
are, then unwind all of the locking, close them all, and then reattempt
the rename.
None of this is really necessary for "typical" filesystems though. It's
mostly of use for NFS, so declare a new export op flag and use that to
determine whether to close the files beforehand.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When we start allowing NFS to be reexported, then we have some problems
when it comes to subtree checking. In principle, we could allow it, but
it would mean encoding parent info in the filehandles and there may not
be enough space for that in a NFSv3 filehandle.
To enforce this at export upcall time, we add a new export_ops flag
that declares the filesystem ineligible for subtree checking.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
With NFSv3 nfsd will always attempt to send along WCC data to the
client. This generally involves saving off the in-core inode information
prior to doing the operation on the given filehandle, and then issuing a
vfs_getattr to it after the op.
Some filesystems (particularly clustered or networked ones) have an
expensive ->getattr inode operation. Atomicity is also often difficult
or impossible to guarantee on such filesystems. For those, we're best
off not trying to provide WCC information to the client at all, and to
simply allow it to poll for that information as needed with a GETATTR
RPC.
This patch adds a new flags field to struct export_operations, and
defines a new EXPORT_OP_NOWCC flag that filesystems can use to indicate
that nfsd should not attempt to provide WCC info in NFSv3 replies. It
also adds a blurb about the new flags field and flag to the exporting
documentation.
The server will also now skip collecting this information for NFSv2 as
well, since that info is never used there anyway.
Note that this patch does not add this flag to any filesystem
export_operations structures. This was originally developed to allow
reexporting nfs via nfsd.
Other filesystems may want to consider enabling this flag too. It's hard
to tell however which ones have export operations to enable export via
knfsd and which ones mostly rely on them for open-by-filehandle support,
so I'm leaving that up to the individual maintainers to decide. I am
cc'ing the relevant lists for those filesystems that I think may want to
consider adding this though.
Cc: HPDD-discuss@lists.01.org
Cc: ceph-devel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: fuse-devel@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This reverts commit a85857633b.
We're still factoring ctime into our change attribute even in the
IS_I_VERSION case. If someone sets the system time backwards, a client
could see the change attribute go backwards. Maybe we can just say
"well, don't do that", but there's some question whether that's good
enough, or whether we need a better guarantee.
Also, the client still isn't actually using the attribute.
While we're still figuring this out, let's just stop returning this
attribute.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
inode_query_iversion() has side effects, and there's no point calling it
when we're not even going to use it.
We check whether we're currently processing a v4 request by checking
fh_maxsize, which is arguably a little hacky; we could add a flag to
svc_fh instead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Minor cleanup, no change in behavior.
Also pull out a common helper that'll be useful elsewhere.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
It doesn't make sense to carry all these extra fields around. Just
make everything into change attribute from the start.
This is just cleanup, there should be no change in behavior.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
inode_query_iversion() can modify i_version. Depending on the exported
filesystem, that may not be safe. For example, if you're re-exporting
NFS, NFS stores the server's change attribute in i_version and does not
expect it to be modified locally. This has been observed causing
unnecessary cache invalidations.
The way a filesystem indicates that it's OK to call
inode_query_iverson() is by setting SB_I_VERSION.
So, move the I_VERSION check out of encode_change(), where it's used
only in GETATTR responses, to nfsd4_change_attribute(), which is
also called for pre- and post- operation attributes.
(Note we could also pull the NFSEXP_V4ROOT case into
nfsd4_change_attribute() as well. That would actually be a no-op,
since pre/post attrs are only used for metadata-modifying operations,
and V4ROOT exports are read-only. But we might make the change in
the future just for simplicity.)
Reported-by: Daire Byrne <daire@dneg.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Since commit b4868b44c5 ("NFSv4: Wait for stateid updates after
CLOSE/OPEN_DOWNGRADE"), every inter server copy operation suffers 5
seconds delay regardless of the size of the copy. The delay is from
nfs_set_open_stateid_locked when the check by nfs_stateid_is_sequential
fails because the seqid in both nfs4_state and nfs4_stateid are 0.
Fix by modifying nfs4_init_cp_state to return the stateid with seqid 1
instead of 0. This is also to conform with section 4.8 of RFC 7862.
Here is the relevant paragraph from section 4.8 of RFC 7862:
A copy offload stateid's seqid MUST NOT be zero. In the context of a
copy offload operation, it is inappropriate to indicate "the most
recent copy offload operation" using a stateid with a seqid of zero
(see Section 8.2.2 of [RFC5661]). It is inappropriate because the
stateid refers to internal state in the server and there may be
several asynchronous COPY operations being performed in parallel on
the same file by the server. Therefore, a copy offload stateid with
a seqid of zero MUST be considered invalid.
Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
linux/fs/nfsd/nfs4proc.c:1542:24: warning: incorrect type in assignment (different base types)
linux/fs/nfsd/nfs4proc.c:1542:24: expected restricted __be32 [assigned] [usertype] status
linux/fs/nfsd/nfs4proc.c:1542:24: got int
Clean-up: The dup_copy_fields() function returns only zero, so make
it return void for now, and get rid of the return code check.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The warning message from nfsd terminating normally
can confuse system adminstrators or monitoring software.
Though it's not exactly fair to pin-point a commit where it
originated, the current form in the current place started
to appear in:
Fixes: e096bbc648 ("knfsd: remove special handling for SIGHUP")
Signed-off-by: kazuo ito <kzpn200@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The handle_inode_event() interface was added as (quoting comment):
"a simple variant of handle_event() for groups that only have inode
marks and don't have ignore mask".
In other words, all backends except fanotify. The inotify backend
also falls under this category, but because it required extra arguments
it was left out of the initial pass of backends conversion to the
simple interface.
This results in code duplication between the generic helper
fsnotify_handle_event() and the inotify_handle_event() callback
which also happen to be buggy code.
Generalize the handle_inode_event() arguments and add the check for
FS_EXCL_UNLINK flag to the generic helper, so inotify backend could
be converted to use the simple interface.
Link: https://lore.kernel.org/r/20201202120713.702387-2-amir73il@gmail.com
CC: stable@vger.kernel.org
Fixes: b9a1b97725 ("fsnotify: create method handle_inode_event() in fsnotify_operations")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Now that all the NFSv4 decoder functions have been converted to
make direct calls to the xdr helpers, remove the unused C macros.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
And clean-up: Now that we have removed the DECODE_TAIL macro from
nfsd4_decode_compound(), we observe that there's no benefit for
nfsd4_decode_compound() to return nfs_ok or nfserr_bad_xdr only to
have its sole caller convert those values to one or zero,
respectively. Have nfsd4_decode_compound() return 1/0 instead.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Refactor for clarity.
Also, remove a stale comment. Commit ed94164398 ("nfsd: implement
machine credential support for some operations") added support for
SP4_MACH_CRED, so state_protect_a is no longer completely ignored.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A dedicated sessionid4 decoder is introduced that will be used by
other operation decoders in subsequent patches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Refactor for clarity.
Note that op_fname is the only instance of an NFSv4 filename stored
in a struct xdr_netobj. Convert it to a u32/char * pair so that the
new nfsd4_decode_filename() helper can be used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Enable nfsd4_decode_opaque() to be used in more decoders, and
replace the READ* macros in nfsd4_decode_opaque().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A dedicated decoder for component4 is introduced here, which will be
used by other operation decoders in subsequent patches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Let's be more careful to avoid overrunning the memory that backs
the bitmap array. This requires updating the synopsis of
nfsd4_decode_fattr().
Bruce points out that a server needs to be careful to return nfs_ok
when a client presents bitmap bits the server doesn't support. This
includes bits in bitmap words the server might not yet support.
The current READ* based implementation is good about that, but that
requirement hasn't been documented.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Because the fattr4 is now managed in an xdr_stream, all that is
needed is to store the initial position of the stream before
decoding the attribute list. Then the actual length of the list
is computed using the final stream position, after decoding is
complete.
No behavior change is expected.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Convert the READ_BUF macro in nfs4xdr.c from open code to instead
use the new xdr_stream-style decoders already in use by the encode
side (and by the in-kernel NFS client implementation). Once this
conversion is done, each individual NFSv4 argument decoder can be
independently cleaned up to replace these macros with C code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
For troubleshooting purposes, record failures to decode NFSv4
operation arguments and encode operation results.
trace_nfsd_compound_decode_err() replaces the dprintk() call sites
that are embedded in READ_* macros that are about to be removed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Start off the conversion to xdr_stream by de-duplicating the functions
that decode void arguments and encode void results.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A "permanent" struct xdr_stream is allocated in struct svc_rqst so
that it is usable by all server-side decoders. A per-rqst scratch
buffer is also allocated to handle decoding XDR data items that
cross page boundaries.
To demonstrate how it will be used, add the first call site for the
new svcxdr_init_decode() API.
As an additional part of the overall conversion, add symbolic
constants for successful and failed XDR operations. Returning "0" is
overloaded. Sometimes it means something failed, but sometimes it
means success. To make it more clear when XDR decoding functions
succeed or fail, introduce symbolic constants.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Fix to return PTR_ERR() error code from the error handling case instead of
0 in function nfsd_file_cache_init(), as done elsewhere in this function.
Fixes: 65294c1f2c5e7("nfsd: add a new struct file caching facility to nfsd")
Signed-off-by: Huang Guobin <huangguobin4@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up.
The file was contributed in 2014 by Christoph Hellwig in commit
31ef83dc05 ("nfsd: add trace events").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Display all currently possible NFSD_MAY permission flags.
Move and rename show_nf_may with a more generic name because the
NFSD_MAY permission flags are used in other places besides the file
cache.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The macro is unused, remove it to tame gcc warning:
fs/nfsd/nfs3proc.c:702:0: warning: macro "nfsd3_fhandleres" is not used
[-Wunused-macros]
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: linux-nfs@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Have the NFSD encoders annotate the boundaries of every
direct-data-placement eligible result data payload. Then change
svcrdma to use that annotation instead of the xdr->page_len
when handling Write chunks.
For NFSv4 on RDMA, that enables the ability to recognize multiple
result payloads per compound. This is a pre-requisite for supporting
multiple Write chunks per RPC transaction.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: "result payload" is a less confusing name for these
payloads. "READ payload" reflects only the NFS usage.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Need to initialize nfsd4_copy's refcount to 1 to avoid use-after-free
warning when nfs4_put_copy is called from nfsd4_cb_offload_release.
Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The source file nfsd_file is not constructed the same as other
nfsd_file's via nfsd_file_alloc. nfsd_file_put should not be
called to free the object; nfsd_file_put is not the inverse of
kzalloc, instead kfree is called by nfsd4_do_async_copy when done.
Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A late paragraph of RFC 1813 Section 3.3.11 states:
| ... if the server does not support the target type or the
| target type is illegal, the error, NFS3ERR_BADTYPE, should
| be returned. Note that NF3REG, NF3DIR, and NF3LNK are
| illegal types for MKNOD.
The Linux NFS server incorrectly returns NFSERR_INVAL in these
cases.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit cc028a10a4 ("NFSD: Hoist status code encoding into XDR
encoder functions") missed a spot.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
has the same arguments as READ but allows the server to return an array
of data and hole extents.
Otherwise it's a lot of cleanup and bugfixes.
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Merge tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"The one new feature this time, from Anna Schumaker, is READ_PLUS,
which has the same arguments as READ but allows the server to return
an array of data and hole extents.
Otherwise it's a lot of cleanup and bugfixes"
* tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux: (43 commits)
NFSv4.2: Fix NFS4ERR_STALE error when doing inter server copy
SUNRPC: fix copying of multiple pages in gss_read_proxy_verf()
sunrpc: raise kernel RPC channel buffer size
svcrdma: fix bounce buffers for unaligned offsets and multiple pages
nfsd: remove unneeded break
net/sunrpc: Fix return value for sysctl sunrpc.transports
NFSD: Encode a full READ_PLUS reply
NFSD: Return both a hole and a data segment
NFSD: Add READ_PLUS hole segment encoding
NFSD: Add READ_PLUS data support
NFSD: Hoist status code encoding into XDR encoder functions
NFSD: Map nfserr_wrongsec outside of nfsd_dispatch
NFSD: Remove the RETURN_STATUS() macro
NFSD: Call NFSv2 encoders on error returns
NFSD: Fix .pc_release method for NFSv2
NFSD: Remove vestigial typedefs
NFSD: Refactor nfsd_dispatch() error paths
NFSD: Clean up nfsd_dispatch() variables
NFSD: Clean up stale comments in nfsd_dispatch()
NFSD: Clean up switch statement in nfsd_dispatch()
...
NFS_FS=y as dependency of CONFIG_NFSD_V4_2_INTER_SSC still have
build errors and some configs with NFSD=m to get NFS4ERR_STALE
error when doing inter server copy.
Added ops table in nfs_common for knfsd to access NFS client modules.
Fixes: 3ac3711adb ("NFSD: Fix NFS server build errors")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Because every path through nfs4_find_file()'s
switch does an explicit return, the break is not needed.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reply to the client with multiple hole and data segments. I use the
result of the first vfs_llseek() call for encoding as an optimization so
we don't have to immediately repeat the call. This also lets us encode
any remaining reply as data if we get an unexpected result while trying
to calculate a hole.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
But only one of each right now. We'll expand on this in the next patch.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
However, we still only reply to the READ_PLUS call with a single segment
at this time.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch adds READ_PLUS support for returning a single
NFS4_CONTENT_DATA segment to the client. This is basically the same as
the READ operation, only with the extra information about data segments.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The original intent was presumably to reduce code duplication. The
trade-off was:
- No support for an NFSD proc function returning a non-success
RPC accept_stat value.
- No support for void NFS replies to non-NULL procedures.
- Everyone pays for the deduplication with a few extra conditional
branches in a hot path.
In addition, nfsd_dispatch() leaves *statp uninitialized in the
success path, unlike svc_generic_dispatch().
Address all of these problems by moving the logic for encoding
the NFS status code into the NFS XDR encoders themselves. Then
update the NFS .pc_func methods to return an RPC accept_stat
value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Refactor: Handle this NFS version-specific mapping in the only
place where nfserr_wrongsec is generated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Refactor: I'm about to change the return value from .pc_func. Clear
the way by replacing the RETURN_STATUS() macro with logic that
plants the status code directly into the response structure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove special dispatcher logic for NFSv2 error responses. These are
rare to the point of becoming extinct, but all NFS responses have to
pay the cost of the extra conditional branches.
With this change, the NFSv2 error cases now get proper
xdr_ressize_check() calls.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd_release_fhandle() assumes that rqstp->rq_resp always points to
an nfsd_fhandle struct. In fact, no NFSv2 procedure uses struct
nfsd_fhandle as its response structure.
So far that has been "safe" to do because the res structs put the
resp->fh field at that same offset as struct nfsd_fhandle. I don't
think that's a guarantee, though, and there is certainly nothing
preventing a developer from altering the fields in those structures.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd_dispatch() is a hot path. Ensure the compiler takes the
processing of rare error cases out of line.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For consistency and code legibility, use a similar organization of
variables as svc_generic_dispatch().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a documenting comment for the function. Remove comments that
simply describe obvious aspects of the code, but leave comments
that explain the differences in processing of each NFS version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reorder the arms so the compiler places checks for the most frequent
case first.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd_dispatch() is a hot path. Let's optimize the XDR method calls
for the by-far common case, which is that the XDR methods are indeed
present.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Follow-up on ten-year-old commit b9081d90f5 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the NFSACL code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There's no protection in nfsd_dispatch() against a NULL .pc_func
helpers. A malicious NFS client can trigger a crash by invoking the
unused/unsupported NFSv2 ROOT or WRITECACHE procedures.
The current NFSD dispatcher does not support returning a void reply
to a non-NULL procedure, so the reply to both of these is wrong, for
the moment.
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Since only the v4 code cares about it, maybe it's better to leave
rq_lease_breaker out of the common dispatch code?
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are actually rare races where this is possible (e.g. if a new open
intervenes between the read of i_writecount and the fi_fds).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The nfsd open code has always kept separate read-only, read-write, and
write-only opens as necessary to ensure that when a client closes or
downgrades, we don't retain more access than necessary.
Also, I didn't realize the cache behaved this way when I wrote
94415b06eb "nfsd4: a client's own opens needn't prevent delegations".
There I assumed fi_fds[O_WRONLY] and fi_fds[O_RDWR] would always be
distinct. The violation of that assumption is triggering a
WARN_ON_ONCE() and could also cause the server to give out a delegation
when it shouldn't.
Fixes: 94415b06eb ("nfsd4: a client's own opens needn't prevent delegations")
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
silence nfscache allocation warnings with kvzalloc
Currently nfsd_reply_cache_init attempts hash table allocation through
kmalloc, and manually falls back to vzalloc if that fails. This makes
the code a little larger than needed, and creates a significant amount
of serial console spam if you have enough systems.
Switching to kvzalloc gets rid of the allocation warnings, and makes
the code a little cleaner too as a side effect.
Freeing of nn->drc_hashtbl is already done using kvfree currently.
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Fixes coccicheck warning:
fs/nfsd/nfs4proc.c:3234:5-29: WARNING: Comparison to bool
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Squelch some sparse warnings:
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16: expected int status
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16: got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24: expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24: got int status
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Squelch some sparse warnings:
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24: expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24: got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32: expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32: got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13: expected restricted __be32 [usertype] err
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13: got int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15: expected unsigned int [assigned] [usertype] count
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15: got restricted __be32 [usertype]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Squelch some sparse warnings:
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13: expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13: got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24: expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24: got int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13: expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13: got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24: expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24: got int err
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reserving space for a large READ payload requires special handling when
reserving space in the xdr buffer pages. One problem we can have is use
of the scratch buffer, which is used to get a pointer to a contiguous
region of data up to PAGE_SIZE. When using the scratch buffer, calls to
xdr_commit_encode() shift the data to it's proper alignment in the xdr
buffer. If we've reserved several pages in a vector, then this could
potentially invalidate earlier pointers and result in incorrect READ
data being sent to the client.
I get around this by looking at the amount of space left in the current
page, and never reserve more than that for each entry in the read
vector. This lets us place data directly where it needs to go in the
buffer pages.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now when a read delegation is given, two delegation related traces
will be printed:
nfsd_deleg_open: client 5f45b854:e6058001 stateid 00000030:00000001
nfsd_deleg_none: client 5f45b854:e6058001 stateid 0000002f:00000001
Although the intention is to let developers know two stateid are
returned, the traces are confusing about whether or not a read delegation
is handled out. So renaming trace_nfsd_deleg_none() to trace_nfsd_open()
and trace_nfsd_deleg_open() to trace_nfsd_deleg_read() to make
the intension clearer.
The patched traces will be:
nfsd_deleg_read: client 5f48a967:b55b21cd stateid 00000003:00000001
nfsd_open: client 5f48a967:b55b21cd stateid 00000002:00000001
Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In nfsd4_encode_listxattrs(), the variable p is assigned to at one point
but this value is never used before p is reassigned. Fix this.
Addresses-Coverity: ("Unused value")
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The delegation is no longer returnable, so I don't think there's much
point retrying the recall.
(I think it's worth asking why we even need separate CLOSED_DELEG and
REVOKED_DELEG states. But treating them the same would currently cause
nfsd4_free_stateid to call list_del_init(&dp->dl_recall_lru) on a
delegation that the laundromat had unhashed but not revoked, incorrectly
removing it from the laundromat's reaplist or a client's dl_recall_lru.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It was an interesting idea but nobody seems to be using it, it's buggy
at this point, and nfs4state.c is already complicated enough without it.
The new nfsd/clients/ code provides some of the same functionality, and
could probably do more if desired.
This feature has been deprecated since 9d60d93198 ("Deprecate nfsd
fault injection").
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a littler helper to make the somewhat arcane bd_contains checks a
little more obvious.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- Eliminate an oops introduced in v5.8
- Remove a duplicate #include added by nfsd-5.9
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Merge tag 'nfsd-5.9-1' of git://git.linux-nfs.org/projects/cel/cel-2.6
Pull nfs server fixes from Chuck Lever:
- Eliminate an oops introduced in v5.8
- Remove a duplicate #include added by nfsd-5.9
* tag 'nfsd-5.9-1' of git://git.linux-nfs.org/projects/cel/cel-2.6:
SUNRPC: remove duplicate include
nfsd: fix oops on mixed NFSv4/NFSv3 client access
If an NFSv2/v3 client breaks an NFSv4 client's delegation, it will hit a
NULL dereference in nfsd_breaker_owns_lease().
Easily reproduceable with for example
mount -overs=4.2 server:/export /mnt/
sleep 1h </mnt/file &
mount -overs=3 server:/export /mnt2/
touch /mnt2/file
Reported-by: Robert Dinse <nanook@eskimo.com>
Fixes: 28df3d1539 ("nfsd: clients don't need to break their own delegations")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208807
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
- Support for user extended attributes on NFS (RFC 8276)
- Further reduce unnecessary NFSv4 delegation recalls
Notable fixes:
- Fix recent krb5p regression
- Address a few resource leaks and a rare NULL dereference
Other:
- De-duplicate RPC/RDMA error handling and other utility functions
- Replace storage and display of kernel memory addresses by tracepoints
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Merge tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6
Pull NFS server updates from Chuck Lever:
"Highlights:
- Support for user extended attributes on NFS (RFC 8276)
- Further reduce unnecessary NFSv4 delegation recalls
Notable fixes:
- Fix recent krb5p regression
- Address a few resource leaks and a rare NULL dereference
Other:
- De-duplicate RPC/RDMA error handling and other utility functions
- Replace storage and display of kernel memory addresses by tracepoints"
* tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6: (38 commits)
svcrdma: CM event handler clean up
svcrdma: Remove transport reference counting
svcrdma: Fix another Receive buffer leak
SUNRPC: Refresh the show_rqstp_flags() macro
nfsd: netns.h: delete a duplicated word
SUNRPC: Fix ("SUNRPC: Add "@len" parameter to gss_unwrap()")
nfsd: avoid a NULL dereference in __cld_pipe_upcall()
nfsd4: a client's own opens needn't prevent delegations
nfsd: Use seq_putc() in two functions
svcrdma: Display chunk completion ID when posting a rw_ctxt
svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()
svcrdma: Introduce Send completion IDs
svcrdma: Record Receive completion ID in svc_rdma_decode_rqst
svcrdma: Introduce Receive completion IDs
svcrdma: Introduce infrastructure to support completion IDs
svcrdma: Add common XDR encoders for RDMA and Read segments
svcrdma: Add common XDR decoders for RDMA and Read segments
SUNRPC: Add helpers for decoding list discriminators symbolically
svcrdma: Remove declarations for functions long removed
svcrdma: Clean up trace_svcrdma_send_failed() tracepoint
...
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Merge tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
- fanotify fix for softlockups when there are many queued events
- performance improvement to reduce fsnotify overhead when not used
- Amir's implementation of fanotify events with names. With these you
can now efficiently monitor whole filesystem, eg to mirror changes to
another machine.
* tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits)
fanotify: compare fsid when merging name event
fsnotify: create method handle_inode_event() in fsnotify_operations
fanotify: report parent fid + child fid
fanotify: report parent fid + name + child fid
fanotify: add support for FAN_REPORT_NAME
fanotify: report events with parent dir fid to sb/mount/non-dir marks
fanotify: add basic support for FAN_REPORT_DIR_FID
fsnotify: remove check that source dentry is positive
fsnotify: send event with parent/name info to sb/mount/non-dir marks
audit: do not set FS_EVENT_ON_CHILD in audit marks mask
inotify: do not set FS_EVENT_ON_CHILD in non-dir mark mask
fsnotify: pass dir and inode arguments to fsnotify()
fsnotify: create helper fsnotify_inode()
fsnotify: send event to parent and child with single callback
inotify: report both events on parent and child with single callback
dnotify: report both events on parent and child with single callback
fanotify: no external fh buffer in fanotify_name_event
fanotify: use struct fanotify_info to parcel the variable size buffer
fsnotify: add object type "child" to object type iterator
fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks
...
The method handle_event() grew a lot of complexity due to the design of
fanotify and merging of ignore masks.
Most backends do not care about this complex functionality, so we can hide
this complexity from them.
Introduce a method handle_inode_event() that serves those backends and
passes a single inode mark and less arguments.
This change converts all backends except fanotify and inotify to use the
simplified handle_inode_event() method. In pricipal, inotify could have
also used the new method, but that would require passing more arguments
on the simple helper (data, data_type, cookie), so we leave it with the
handle_event() method.
Link: https://lore.kernel.org/r/20200722125849.17418-9-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The 'inode' argument to handle_event(), sometimes referred to as
'to_tell' is somewhat obsolete.
It is a remnant from the times when a group could only have an inode mark
associated with an event.
We now pass an iter_info array to the callback, with all marks associated
with an event.
Most backends ignore this argument, with two exceptions:
1. dnotify uses it for sanity check that event is on directory
2. fanotify uses it to report fid of directory on directory entry
modification events
Remove the 'inode' argument and add a 'dir' argument.
The callback function signature is deliberately changed, because
the meaning of the argument has changed and the arguments have
been documented.
The 'dir' argument is set to when 'file_name' is specified and it is
referring to the directory that the 'file_name' entry belongs to.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Drop the repeated word "the" in a comment.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We hold the cl_lock here, and that's enough to keep stateid's from going
away, but it's not enough to prevent the files they point to from going
away. Take fi_lock and a reference and check for NULL, as we do in
other code.
Reported-by: NeilBrown <neilb@suse.de>
Fixes: 78599c42ae ("nfsd4: add file to display list of client's opens")
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
If the rpc_pipefs is unmounted, then the rpc_pipe->dentry becomes NULL
and dereferencing the dentry->d_sb will trigger an oops. The only
reason we're doing that is to determine the nfsd_net, which could
instead be passed in by the caller. So do that instead.
Fixes: 11a60d1592 ("nfsd: add a "GetVersion" upcall for nfsdcld")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We recently fixed lease breaking so that a client's actions won't break
its own delegations.
But we still have an unnecessary self-conflict when granting
delegations: a client's own write opens will prevent us from handing out
a read delegation even when no other client has the file open for write.
Fix that by turning off the checks for conflicting opens under
vfs_setlease, and instead performing those checks in the nfsd code.
We don't depend much on locks here: instead we acquire the delegation,
then check for conflicts, and drop the delegation again if we find any.
The check beforehand is an optimization of sorts, just to avoid
acquiring the delegation unnecessarily. There's a race where the first
check could cause us to deny the delegation when we could have granted
it. But, that's OK, delegation grants are optional (and probably not
even a good idea in that case).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A single character (line break) should be put into a sequence.
Thus use the corresponding function "seq_putc()".
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Check if user extended attributes are supported for an inode,
and return the answer when being queried for file attributes.
An exported filesystem can now signal its RFC8276 user extended
attributes capability.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Implement the main entry points for the *XATTR operations.
Add functions to calculate the reply size for the user extended attribute
operations, and implement the XDR encode / decode logic for these
operations.
Add the user extended attributes operations to nfsd4_ops.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Add the structures used in extended attribute request / response handling.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Since the NFSv4.2 extended attributes extension defines 3 new access
bits for xattr operations, take them in to account when validating
what the client is asking for, and when checking permissions.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This adds the filehandle based functions for the xattr operations
that call in to the vfs layer to do the actual work.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
[ cel: address checkpatch.pl complaint ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Add defines for server-side extended attribute support. Most have
already been added as part of client support, but these are
the network order error codes for the noxattr and xattr2big errors,
and the addition of the xattr support to the supported file
attributes (if configured).
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfs4_decode_write has code to parse incoming XDR write data in to
a kvec head, and a list of pages.
Put this code in to a separate function, so that it can be used
later by the xattr code, for setxattr. No functional change.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I don't understand this code well, but I'm seeing a warning about a
still-referenced inode on unmount, and every other similar filesystem
does a dput() here.
Fixes: e8a79fb14f ("nfsd: add nfsd/clients directory")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We don't drop the reference on the nfsdfs filesystem with
mntput(nn->nfsd_mnt) until nfsd_exit_net(), but that won't be called
until the nfsd module's unloaded, and we can't unload the module as long
as there's a reference on nfsdfs. So this prevents module unloading.
Fixes: 2c830dd720 ("nfsd: persist nfsd filesystem across mounts")
Reported-and-Tested-by: Luo Xiaogang <lxgrxd@163.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The server is failing to apply the umask when creating new objects on
filesystems without ACL support.
To reproduce this, you need to use NFSv4.2 and a client and server
recent enough to support umask, and you need to export a filesystem that
lacks ACL support (for example, ext4 with the "noacl" mount option).
Filesystems with ACL support are expected to take care of the umask
themselves (usually by calling posix_acl_create).
For filesystems without ACL support, this is up to the caller of
vfs_create(), vfs_mknod(), or vfs_mkdir().
Reported-by: Elliott Mitchell <ehem+debian@m5p.com>
Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Tested-by: Salvatore Bonaccorso <carnil@debian.org>
Fixes: 47057abde5 ("nfsd: add support for the umask attribute")
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
- Keep nfsd clients from unnecessarily breaking their own delegations:
Note this requires a small kthreadd addition, discussed at:
https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com
The result is Tejun Heo's suggestion, and he was OK with this going
through my tree.
- Patch nfsd/clients/ to display filenames, and to fix byte-order when
displaying stateid's.
- fix a module loading/unloading bug, from Neil Brown.
- A big series from Chuck Lever with RPC/RDMA and tracing improvements,
and lay some groundwork for RPC-over-TLS.
Note Stephen Rothwell spotted two conflicts in linux-next. Both should
be straightforward:
include/trace/events/sunrpc.h
https://lore.kernel.org/r/20200529105917.50dfc40f@canb.auug.org.au
net/sunrpc/svcsock.c
https://lore.kernel.org/r/20200529131955.26c421db@canb.auug.org.au
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Merge tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Highlights:
- Keep nfsd clients from unnecessarily breaking their own
delegations.
Note this requires a small kthreadd addition. The result is Tejun
Heo's suggestion (see link), and he was OK with this going through
my tree.
- Patch nfsd/clients/ to display filenames, and to fix byte-order
when displaying stateid's.
- fix a module loading/unloading bug, from Neil Brown.
- A big series from Chuck Lever with RPC/RDMA and tracing
improvements, and lay some groundwork for RPC-over-TLS"
Link: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com
* tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux: (49 commits)
sunrpc: use kmemdup_nul() in gssp_stringify()
nfsd: safer handling of corrupted c_type
nfsd4: make drc_slab global, not per-net
SUNRPC: Remove unreachable error condition in rpcb_getport_async()
nfsd: Fix svc_xprt refcnt leak when setup callback client failed
sunrpc: clean up properly in gss_mech_unregister()
sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations.
sunrpc: check that domain table is empty at module unload.
NFSD: Fix improperly-formatted Doxygen comments
NFSD: Squash an annoying compiler warning
SUNRPC: Clean up request deferral tracepoints
NFSD: Add tracepoints for monitoring NFSD callbacks
NFSD: Add tracepoints to the NFSD state management code
NFSD: Add tracepoints to NFSD's duplicate reply cache
SUNRPC: svc_show_status() macro should have enum definitions
SUNRPC: Restructure svc_udp_recvfrom()
SUNRPC: Refactor svc_recvfrom()
SUNRPC: Clean up svc_release_skb() functions
SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives
SUNRPC: Replace dprintk() call sites in TCP receive path
...
This can only happen if there's a bug somewhere, so let's make it a WARN
not a printk. Also, I think it's safest to ignore the corruption rather
than trying to fix it by removing a cache entry.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
PF_LESS_THROTTLE exists for loop-back nfsd (and a similar need in the
loop block driver and callers of prctl(PR_SET_IO_FLUSHER)), where a
daemon needs to write to one bdi (the final bdi) in order to free up
writes queued to another bdi (the client bdi).
The daemon sets PF_LESS_THROTTLE and gets a larger allowance of dirty
pages, so that it can still dirty pages after other processses have been
throttled. The purpose of this is to avoid deadlock that happen when
the PF_LESS_THROTTLE process must write for any dirty pages to be freed,
but it is being thottled and cannot write.
This approach was designed when all threads were blocked equally,
independently on which device they were writing to, or how fast it was.
Since that time the writeback algorithm has changed substantially with
different threads getting different allowances based on non-trivial
heuristics. This means the simple "add 25%" heuristic is no longer
reliable.
The important issue is not that the daemon needs a *larger* dirty page
allowance, but that it needs a *private* dirty page allowance, so that
dirty pages for the "client" bdi that it is helping to clear (the bdi
for an NFS filesystem or loop block device etc) do not affect the
throttling of the daemon writing to the "final" bdi.
This patch changes the heuristic so that the task is not throttled when
the bdi it is writing to has a dirty page count below below (or equal
to) the free-run threshold for that bdi. This ensures it will always be
able to have some pages in flight, and so will not deadlock.
In a steady-state, it is expected that PF_LOCAL_THROTTLE tasks might
still be throttled by global threshold, but that is acceptable as it is
only the deadlock state that is interesting for this flag.
This approach of "only throttle when target bdi is busy" is consistent
with the other use of PF_LESS_THROTTLE in current_may_throttle(), were
it causes attention to be focussed only on the target bdi.
So this patch
- renames PF_LESS_THROTTLE to PF_LOCAL_THROTTLE,
- removes the 25% bonus that that flag gives, and
- If PF_LOCAL_THROTTLE is set, don't delay at all unless the
global and the local free-run thresholds are exceeded.
Note that previously realtime threads were treated the same as
PF_LESS_THROTTLE threads. This patch does *not* change the behvaiour
for real-time threads, so it is now different from the behaviour of nfsd
and loop tasks. I don't know what is wanted for realtime.
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Chuck Lever <chuck.lever@oracle.com> [nfsd]
Cc: Christoph Hellwig <hch@lst.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Link: http://lkml.kernel.org/r/87ftbf7gs3.fsf@notabene.neil.brown.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto updates from Herbert Xu:
"API:
- Introduce crypto_shash_tfm_digest() and use it wherever possible.
- Fix use-after-free and race in crypto_spawn_alg.
- Add support for parallel and batch requests to crypto_engine.
Algorithms:
- Update jitter RNG for SP800-90B compliance.
- Always use jitter RNG as seed in drbg.
Drivers:
- Add Arm CryptoCell driver cctrng.
- Add support for SEV-ES to the PSP driver in ccp"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (114 commits)
crypto: hisilicon - fix driver compatibility issue with different versions of devices
crypto: engine - do not requeue in case of fatal error
crypto: cavium/nitrox - Fix a typo in a comment
crypto: hisilicon/qm - change debugfs file name from qm_regs to regs
crypto: hisilicon/qm - add DebugFS for xQC and xQE dump
crypto: hisilicon/zip - add debugfs for Hisilicon ZIP
crypto: hisilicon/hpre - add debugfs for Hisilicon HPRE
crypto: hisilicon/sec2 - add debugfs for Hisilicon SEC
crypto: hisilicon/qm - add debugfs to the QM state machine
crypto: hisilicon/qm - add debugfs for QM
crypto: stm32/crc32 - protect from concurrent accesses
crypto: stm32/crc32 - don't sleep in runtime pm
crypto: stm32/crc32 - fix multi-instance
crypto: stm32/crc32 - fix run-time self test issue.
crypto: stm32/crc32 - fix ext4 chksum BUG_ON()
crypto: hisilicon/zip - Use temporary sqe when doing work
crypto: hisilicon - add device error report through abnormal irq
crypto: hisilicon - remove codes of directly report device errors through MSI
crypto: hisilicon - QM memory management optimization
crypto: hisilicon - unify initial value assignment into QM
...
Linus Torvalds